photos now zoom to the level that maximizes how much of it is displayed without leaving any whitespace
added functionality for storing most recently viewed photos
added functionality for storing most recently viewed photos
added functionality for storing most recently viewed photos
added function for getting reuse identifier to support inheritance; updated name of selector to perform in segue to match changes in PhotoViewController
renamed imageURL to photoURL
made the recent photos table view use dynamic prototype cells and named the transition from recent photos list to photo view